/*
 *  Copyright 2013 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

package org.webrtc;

/**
 * Java wrapper for a C++ MediaSourceInterface.
 */
public class MediaSource {
    /**
     * Tracks MediaSourceInterface.SourceState
     */
    public enum State {
        INITIALIZING,
        LIVE,
        ENDED,
        MUTED;

        @CalledByNative("State")
        static State fromNativeIndex(int nativeIndex) {
            return values()[nativeIndex];
        }
    }

    private final RefCountDelegate refCountDelegate;
    private long nativeSource;

    public MediaSource(long nativeSource) {
        refCountDelegate = new RefCountDelegate(() -> JniCommon.nativeReleaseRef(nativeSource));
        this.nativeSource = nativeSource;
    }

    public State state() {
        checkMediaSourceExists();
        return nativeGetState(nativeSource);
    }

    public void dispose() {
        checkMediaSourceExists();
        refCountDelegate.release();
        nativeSource = 0;
    }

    /**
     * Returns a pointer to webrtc::MediaSourceInterface.
     */
    protected long getNativeMediaSource() {
        checkMediaSourceExists();
        return nativeSource;
    }

    /**
     * Runs code in {@code runnable} holding a reference to the media source. If the object has
     * already been released, does nothing.
     */
    void runWithReference(Runnable runnable) {
        if (refCountDelegate.safeRetain()) {
            try {
                runnable.run();
            } finally {
                refCountDelegate.release();
            }
        }
    }

    private void checkMediaSourceExists() {
        if (nativeSource == 0) {
            throw new IllegalStateException("MediaSource has been disposed.");
        }
    }

    private static native State nativeGetState(long pointer);
}
